Patterns of growth in human septal cartilage: a review of new approaches.

Recent results of the growth activities of the septal cartilage in children, adolescents, and adults are reviewed. Cartilaginous biopsies were obtained during septoplasty . Matrix synthesis was measured by in vitro incorporation of labeled sulphate; DNA synthesis was measured by in vitro incorporation of labeled thymidine. The cell density of the septal cartilage was determined by cell counting, and chondrocytes were grown in culture in an assay to determine the number of chondrocytes capable of proliferation. With data from these 4 types of experiments 5 different areas could be distinguished in human septal cartilage: (1) anterior free end, (2) suprapremaxillary area, (3) central area, (4) posterior area, and (5) caudal prolongation. Metabolic activities, degree of cell replication, and proliferative capacity are highest in childhood in all areas; they decline with age, but remain surprisingly high in the central area and in the anterior free end, even in adults. These results help to explain some clinical observations and may help the rhinosurgeon in his decision to resect the septal cartilage, especially in children.